小麦中的过敏原在酱油酿造过程中的降解分析

目的 探究低盐固态酱油酿造过程不同阶段小麦过敏原的变化。方法 采用实验室模拟方法酿造低盐固态酱油, 采集酿造过程中的原料小麦面粉和制曲阶段14、27、36和44 h时的样品, 发酵阶段5、10、17、24和30 d, 灭菌前和灭菌后12个样品, 用实验室制备的小麦蛋白的多克隆抗体、免疫球蛋白G以及从医院获得的小麦过敏病人血清免疫球蛋白E对样品进行十二烷基硫酸钠聚丙烯酰胺凝胶电泳、免疫印迹和酶联免疫测定不同阶段样品的免疫原性。结果 经制曲、发酵处理和加热灭菌处理后, 凝胶电泳图中小麦面粉中的蛋白条带逐渐减少甚至消失, 其中制曲阶段变化程度最大。小麦过敏蛋白中的主要组分麦醇溶蛋白和麦谷蛋白在制曲阶段后期免疫印迹条带逐渐消失, 在进入发酵阶段第5 d时已完全检测不到免疫印迹条带。酶联免疫实验结果表明, 与未处理小麦面粉样品相比, 制曲、发酵和灭菌等处理过程均会不同程度降低小麦过敏原的抗原性和过敏原性, 在进入发酵阶段的第24 d小麦过敏蛋白含量已低于20 mg/kg, 致敏性基本被消除。结论 在实验室模拟低盐固态酱油酿造中, 小麦过敏蛋白的抗原性和过敏原性在制曲、发酵和灭菌等过程均不同程度降低, 其中制曲阶段作用最大, 成品酱油中小麦的致敏性基本被消除。     

小麦致敏蛋白及其过敏病症研究进展

小麦作为世界上重要的粮食作物之一,其过敏原对人体的健康有重大的影响。不同的小麦蛋白,经过不同的致敏途径,可能导致不同的小麦过敏病症。主要对小麦致敏蛋白的种类和小麦过敏病症进行综述。     

小麦食源性过敏原致敏亚基分析

通过SDS-PAGE对小麦亚基成分分析,采用ImmunoCAP 250全自动体外免疫检测系统测定小麦过敏患者不同个体对小麦致敏蛋白的识别结果,并以我国12例小麦过敏患者的血清为探针,3例正常人的血清池为对照,与师栾02-1小麦粉进行还原态一维电泳免疫印迹分析,鉴定引起我国小麦过敏人群过敏的小麦过敏原及其致敏概率。结果表明,小麦过敏原蛋白亚基的致敏概率自高至低的顺序依次为17 ku(6/12)、28ku(6/12)、14ku(5/12)、19ku(5/12)、22ku(5/12)、24ku(5/12)、25 ku(5/12)、26ku(5/12)、11 ku(4/12)、12ku(4/12)、16 ku(4/12)、21 ku(4/12)、27 ku(4/12)、18 ku(3/12)、30 ku(3/12)、31 ku(3/12)、36ku(3/12)、47ku(3/12)、83ku(3/12),其他一些蛋白亚基致敏概率为1/6或1/12。     

小麦过敏原抗原抑制技术研究进展

食物过敏是全球范围内被广泛关注的食品安全问题之一。小麦是世界上生产和消费最广泛的食物之一,同时也是公认的八大过敏性食品之一,食用小麦会诱发多种过敏症状。麦醇溶蛋白和麦谷蛋白是小麦中主要过敏原,在它们链结构中,重复的氨基酸序列区域存在大量抗原表位,摄入或接触均可能会诱发过敏反应。对小麦中的主要过敏原、过敏病症和现阶段过敏原的检测方法以及抑制过敏原抗原性的方法进行了综述。为低敏性小麦制品的开发提供参考。     

小麦蛋白组分及其对加工品质的影响

蛋白质是小麦籽粒的主要营养成分,也是评价小麦品质的重要指标。通常按溶解性不同,将小麦蛋白分为清蛋白、球蛋白、醇溶蛋白和麦谷蛋白,小麦品质与各蛋白组分含量和比例密切相关。本文从蛋白组分的组成结构、积累规律、影响因素和对加工品质的影响等方面,对小麦蛋白各组分的研究应用进行了总结,并对其研究前景进行了展望。     

不同重金属胁迫对小麦金属硫蛋白同源性的影响

用不同浓度的CoCl2、HgCl2、CuSO4、Pb(AC)2处理小麦,研究了重金属胁迫对小麦生长和金属硫蛋白同源性的影响。结果表明:重金属胁迫24h后,小麦叶片即出现伤害症状。不同重金属胁迫小麦产生的金属硫蛋白具有广泛的同源性,对金属硫蛋白的诱导强度也不同。     

小麦面筋蛋白改性技术的研究

小麦面筋蛋白来源广泛,价格低廉,是良好的植物蛋白资源。综述了小麦面筋蛋白的改性技术,分别介绍了物理方法、化学方法、生物酶法以及基因工程法,不同的改性方法对小麦面筋蛋白的功能特性均有了较大程度的改变。对不同的改性方法的优缺点也做了简要描述。从国内外的研究情况来看小麦面筋蛋白的应用前景是十分广阔的。     

非糊化条件对小麦蛋白肽酶法制备的影响

为了探讨联合制备小麦蛋白肽和小麦淀粉的新方法,以小麦面粉为原料,以小麦蛋白肽的纯度、得率、水解度、还原糖质量分数为评价指标,研究了淀粉非糊化状态下不同处理条件对两种蛋白酶制备小麦蛋白肽的作用效果。结果表明：与浸泡前加酶相比,浸泡后加酶生产的蛋白肽纯度高,还原糖质量分数低,但两者得率相差较小。最佳浸泡条件为：温度50 ℃,时间2.5 h。此条件下,中性蛋白酶水解得到的小麦蛋白肽纯度为27%,得率为75%,水解度为17.6%,还原糖质量分数为5.9%;碱性蛋白酶水解得到的小麦蛋白肽纯度为25%,得率为85%,水解度为23.7%,还原糖质量分数为9%。预处理过程中,宜采用浸泡后加酶。可根据需要选择不同蛋白酶生产,但碱性蛋白酶中淀粉酶含量较高会产生相对多的淀粉糖。     

小麦胚芽蛋白制备及应用

小麦胚芽蛋白是一种完全蛋白,其氨基酸全面平衡,且易于被人体吸收,在营养学上具有重要意义。该文主要对小麦胚芽蛋白营养价值、制备及其应用进行综述。     

热加工对小麦蛋白结构和消化特性的影响

研究100℃热处理不同时间（5min、15min、30min）对小麦蛋白分子结构及其体外消化的影响。结果表明,随着热处理时间的增加,麦谷蛋白和麦醇溶蛋白的α-螺旋结构逐渐减少,无规则卷曲结构的相对含量分别增加了8.2%、7.98%,这与小麦蛋白的电镜微观结果一致;麦谷蛋白与麦醇溶蛋白的平均粒径在热处理30min时分别达到了237.4μm、254.3μm;根据凝胶电泳结果显示,热处理对麦醇溶蛋白和麦谷蛋白的亚基分子量没有显著影响;在特定的热处理时间内,小麦蛋白的消化程度与加热时间呈正比关系。综上,麦醇溶蛋白与麦谷蛋白在热处理下发生的结构变化具有一致性,且在100℃ 30min处理下的小麦蛋白具有最高的消化率。     

“哈师”黑粒小麦全麦粉的品质评价

对“哈师”黑粒小麦的千粒质量与制粉进行测试,研究其全麦粉的理化指标、面筋含量及特性、流变学特性。结果表明：“哈师”黑粒小麦的千粒质量为30.11g,出粉率达75%,其全麦粉的蛋白质含量为18.56%,干、湿面筋含量分别为28.79%和64.55%,远远高于普通小麦粉,但面筋弹性一般。面团吸水率为67.6%,面团形成为3.0min,稳定时间2.1min,弱化度119FU,粉质评价值40。面团流变性低于普通小麦粉。综合判断,“哈师”黑粒小麦适宜加工成面条。     

Effects of Enzymatic Hydrolysis of Protein on the Pasting Properties of Different Types of Wheat Flour

Abstract: As one of the most effective methods to modify proteins, enzymatic hydrolysis is used widely in the preparation of wheat products in the food industry. During the same process, starch pasting occurs frequently. The effects of wheat protein hydrolysis with papain, pepsin, and trypsin on the pasting properties of 3 different kinds of flour were investigated in 5 concentrations. Results showed that the peak viscosity, trough, final, and integral area of pasting curve of these flours decreased with increasing enzymatic hydrolysis of protein, and decreased significantly with the increasing enzyme concentrations. Medium‐gluten flour was the least sensitive to enzymatic activity and weak‐gluten the most sensitive. Downtrends appeared with increasing papain and trypsin concentrations in the form of breakdown. Enzymes had no significant different effect on the peak times of strong‐ and medium‐gluten flour, but prolonged peak time slightly in weak‐gluten flour. The pasting time and temperature of strong‐ and medium‐gluten flour were significantly increased in a concentration‐dependent manner. However, there were no significant effects on the pasting times of weak‐gluten flour. These results could supply a basis for utilization of enzymatic hydrolysis of wheat protein in food industry and for further studies into the interactions between hydrolyzed protein and starch in food or processing industries. Practical Application: Illuminating the effects of enzymatic hydrolysis of protein on the pasting properties of different types of wheat flour is very important in food industry. Flour viscosity decreases after enzymatic hydrolysis of protein/gluten. Enzymes have different effects on peak time, pasting time, and pasting temperatures for different types of flour. These results could supply a basis for utilization of enzymatic hydrolysis of wheat protein in food industry and for further studies into the interactions between hydrolyzed protein and starch in food or processing industries.     

Protein Characteristics that Affect the Quality of Vital Wheat Gluten to be Used in Baking: A Review

The use of vital wheat gluten in the baking industry and wheat flour mills aims to improve the rheological characteristics of flour considered unsuitable to obtain products such as sliced bread, French bread, high‐fiber breads, and other products that require strong flours. To improve characteristics such as flour strength, dough mixing tolerance, and bread volume, vital wheat gluten is added to flour at levels that can vary from 2% to 10% (flour basis), with 5% being a commonly used dosage. However, the vital wheat gluten commercialized in the market has few quality specifications, especially related to the characteristics of the proteins that constitute it and are responsible for the formation of the viscoelastic gluten network. Information on protein quality is important, because variations are observed in the technological quality of vital wheat gluten obtained from different sources, which could be associated to damage caused to proteins during the obtainment process. Several tests, either physical–chemical analyses, or rheological tests, are carried out to establish gluten quality; however, they are sometimes time‐consuming and costly. Although these tests give good answers to specify gluten quality, flour mills, and the baking industries require fast and simple tests to evaluate the uses and/or dosage of vital gluten addition to wheat flour. This review covers the concepts, uses, obtainment processes, and quality analysis of vital wheat gluten, as well as simple tests to help identify details about protein quality of commercial vital wheat gluten.     

PHYSICAL PROPERTIES OF SUGAR-SNAP COOKIES USING GRANULE SURFACE DEPROTEINATED WHEAT STARCH

The physical properties of soft wheat starch granule surface proteins and soy flours or isolates, which contribute to the texture of sugar‐snap cookies was studied. Soft wheat flour was deproteinated and cookies were produced containing 0, 10, 20 or 30% soy flour, or one of two types of ground, textured soy flour. Color, fracture force and spread ratio of cookies were determined. Cookies formulated with wheat starch stripped of the starch granule surface proteins exhibited significant alterations in diameter, fracture force, thickness and surface cracking. Cookies containing ground, textured soy flour and protein‐stripped starch granule wheat flour were larger, thinner and had more surface cracking than those produced with nontextured soy flour. Wheat starch granule surface proteins appear to partially mediate the interaction of proteins and starch in a sugar‐snap cookie system.     

Effects of ball‐milling on the glass transition of wheat flour constituents

BACKGROUND: Starch and gluten, the major components of wheat flour, greatly influence the structural characteristics of food products made with wheat flour. The effects of ball‐milling on the change in the semicrystalline structure of starch granules to the amorphous state have been reported. However, the effects of ball‐milling of native wheat flour on physicochemical changes in wheat flour constituents have not been elucidated. Therefore in this study the effects of ball‐milling on the glass transition of wheat flour constituents were investigated. RESULTS: Crude gluten, non‐gluten proteins and separated starch were obtained from wheat flour ball‐milled for 0–10 h, and the glass transition temperature (T_g) of these constituents was evaluated. The T_g of all wheat flour constituents decreased with increasing ball‐milling time. Sodium dodecyl sulfate polyacrylamide gel electrophoresis revealed that changes in band position and intensity did not occur for gluten but did occur for non‐gluten proteins. X‐ray diffraction revealed decreased crystallinity and greater plasticisation by water in separated starch as the ball‐milling time was prolonged. CONCLUSION: The results showed that the ball‐milling process decreased the T_g of wheat flour constituents as a function of milling time. The decrease in T_g was probably due to changes in conformation of protein subunits in gluten and depolymerisation of the non‐gluten protein fraction. The information obtained here about the physical alteration of wheat flour constituents may enhance the ability to successfully use ball‐milled wheat flour in food applications. Copyright © 2008 Society of Chemical Industry     

添加糯小麦粉对小麦粉及其面条品质特性的影响

糯小麦与普通小麦的主要差异是糯小麦不含直链淀粉或其含量很低,其对面制品的制作品质产生一定的影响。本研究利用"济糯1号"分别与"济麦20"和"济麦22"按20%、40%、60%和80%的添加量进行配粉,研究糯小麦粉对普通小麦粉品质特性的影响及其面条制品品质的改良作用。结果表明:"济糯1号"的淀粉糊化回升值为449 c P,显著低于"济麦20"和"济麦22";籽粒硬度达64.89,籽粒蛋白质含量(干基)达16.14%,面筋指数为66.08%,粉质仪稳定时间为2.00 min,鲜面条色泽变化小,2 h和24 h的ΔE*分别为3.83和5.29;"济糯1号"与"济麦20"的配粉中,随糯小麦粉添加量的增加,配粉的淀粉回升值降低,面筋指数降低,吸水率增加,面团稳定时间变短,鲜面条色泽2 h和24 h的ΔE*逐渐变小,配粉面条的适口性和光滑性更好;"济糯1号"与"济麦22"的配粉中,随糯小麦粉添加量的增加,面粉蛋白含量增加、面筋指数升高、吸水率增加、淀粉糊化的回升值降低,鲜面条色泽2 h和24 h的ΔE*逐渐变小,配粉的面条制作品质好,面条的适口性和光滑性均改善;糯小麦粉的添加使配粉的面粉品质特性和淀粉特性更有利于面条制作品质的改良,"济糯1号"适宜添加量为20%~40%。     

小麦淀粉结构、组成、改性对其理化性能及面条品质的影响研究进展

淀粉是小麦粉中主要组分,其在结构和组成上的变化会引起小麦淀粉功能特性的改变,进而影响小麦粉面条特性。本文介绍了近年来小麦淀粉在结构、组成、改性上的研究进展,总结了小麦面粉中淀粉在结构和组成上变化对面条品质的影响,为面条专用粉加工和小麦育种提供一定的理论基础。     

鸡枞全麦面粉试制及其特性

据现有文献资料试制鸡枞全麦面粉,主要研究预煮时间和接种方式及接种量确定,结果表明:预煮15 min可使麦粒水分含量适宜,经分装、灭菌后,接种1%～2%(V/W)液体菌种,在26℃恒温培养,菌丝体萌发速度快、长势好、生长迅速,在20 d可长满麦粒表面。长满菌丝体麦粒经烘干、粉碎后可得感官品质良好的鸡枞全麦面粉。特性测定结果显示,制得鸡枞全麦面粉较原麦全麦面粉蛋白质含量增加,而面筋含量和质量下降,适于制作蛋糕和糕点。     

河南省小麦和小麦粉中铝本底调查研究

了解河南省小麦和小麦粉中铝本底情况,为监管部门防控措施提供依据,为小麦及其制品中含铝标准修订提供帮助。在河南省17个地市共采集了569份小麦、小麦粉和麸皮样品,样品直接从农户家或者农村小磨坊中获取,确认没有添加含铝添加剂后采集。采用电感耦合等离子体质谱法(ICP-MS)检测铝含量。检测结果显示,小麦、小麦粉和麸皮中铝含量的平均值分别为30.92 mg/kg、15.14mg/kg和58.32mg/kg,结果表明小麦中铝元素主要集中在麸皮中。调查结果为相关生产加工者和食品安全监管部门对小麦粉及其制品的生产加工和监管提供技术支撑,结合当地实际情况,还可为制订适合本地的小麦及其制品等相关食品安全标准制修订提供基础数据。     

小麦粉的基础营养与品质改善

小麦粉的基础营养源于小麦又不同于小麦,淀粉及蛋白因去掉了麸皮比小麦大,也因麸皮带走了食用纤维素、维生素和矿物质而造成营养损失,改善小麦粉的基础营养是急待解决的课题。